Clearing up the turf could cost hundreds of pounds
The entire sixth year of a school was sent home on their last day after pupils turfed over the floor of their common room.
Teachers at Banchory Academy took the step after it was discovered some pupils had been drinking.
Aberdeenshire Council said it was decided to send all 100 pupils home.
A spokesman said there were concerns about disruption to exams taking place in the school. One 17-year-old pupil was charged with breach of the peace.
An Aberdeenshire Council spokesman said: "Banchory Academy is extremely disappointed that the disruptive actions of a number of sixth year pupils has spoiled what was due to be an enjoyable day of activities to mark their last day of term.
"There was evidence that some pupils had been drinking and given the size of the year group the head teacher has had no choice but to send all of them home, both for their own safety and to avoid any disruption to standard grade exams under way today.
"This will be particularly disappointing for those sixth years who were genuinely looking forward to their last day of term."
The spokesman added: "A day of activities had been planned to but due to the actions of a minority of pupils this has had to be cancelled.
"This is a very poor way for pupils to end their school career and we hope those who disrupted the day understand the upset their actions have caused."
The cost of clearing up the turf has been estimated at hundreds of pounds.